execute

This method actually performs the command, when the given parsed
set of command-line words. The commands list is almost always the
set of strings, starting with the access word that triggered the
command. Some commands have custom APIs however, that allow almost
anything to be in the commands list, or even for the commands to be null.
This method is not allowed to be called until the player or mob has
satisfied the actionsCost requirements and the securityCheck

executeInternal

This method is used for making "insider" calls to the command. It's parameters
and implementation can follow any rules you like. The engine will sometimes
use these to make direct calls to the command implementations.